Umbrella stand base assembly



FIG. 1 is an exploded top perspective of an umbrella stand base assembly showing my new design;

FIG. 2 is a top perspective view of;

FIG. 3 is a front elevational view thereof;

FIG. 4 is a right side elevational view, the left side being a mirror image; and,

FIG. 5 is a top plan view thereof.

The broken lines shown in FIGS. 1-5 indicate indeterminate thickness. They are otherwise for illustrative purposes only and indicate the nature and use of my new design. The bottom of the umbrella stand base assembly of my new design is unornamented and is not considered part of my new design. 

The ornamental design for an umbrella stand base assembly, as shown and described. 